Predictors of prolonged mechanical ventilation in a cohort of 5123 cardiac surgical patients:

Amiodarone use and prolonged mechanical ventilation after cardiac surgery: a single-center analysis

BACKGROUND

Prolonged mechanical ventilation (PMV) after cardiac surgery increases the risk of complications such as pulmonary atelectasis and ventilator-associated pneumonia. This study aims to investigate the risk factors associated with delayed extubation, including the impact of cardiovascular medication.

METHOD

This retrospective, single-center study analyzed 1,976 patients who underwent open heart surgery at Nanjing Drum Tower Hospital from October 2020 to January 2023. Patients were categorized into early extubation (n = 1071) and delayed extubation (n = 905) groups. Multivariate logistic regression was employed to identify risk factors for delayed extubation. Amiodarone were indicated to be associated with delayed extubation. To further address bias, we derived a propensity score predicting the function of Amiodarone on delayed extubation, and matched 228 cases to 684 controls with similar risk profiles.

RESULTS

Multivariate analysis confirmed that hypertension, stroke, amiodarone use, age, LVEF, CPB time, and DHCA were significant predictors of delayed extubation. Postoperative use of amiodarone was significantly associated with delayed extubation (OR:1.753, 95%CI: 1.287-2.395, P < 0.001). PSM analysis further confirmed that patients receiving amiodarone had longer ventilation times, prolonged hospital stays, and higher in-hospital mortality.

CONCLUSION

Postoperative use of amiodarone is a significant predictor of delayed extubation, warranting careful consideration in clinical practice. Further research is needed to clarify the causal relationship between amiodarone use and extubation outcomes.

Risk Factors of Prolonged Mechanical Ventilation in Post Coronary Artery Bypass Graft Patients: A Scoping Review

Prolonged mechanical ventilation (PMV) following CABG surgery is associated with increased patient morbidity and mortality. A consensus has yet to be reached regarding the time limit for PMV. Various studies have identified factors that influence PMV in patients following CABG surgery, but a review has yet to synthesize the results systematically. This review aimed to identify the definition and factors associated with PMV in patients following isolated CABG surgery. This scoping review used the framework developed by Arksey and O'Malley (2005). Primary sources of information were searched through 5 databases: PubMed, Scopus, Oxford Academy, Sage, and CINAHL and two search engines: Science Direct and Google Scholar, accessed on October 25, 2023. Eight articles with a total of 12,178 participants were included in this review. The PMV time limits used in the studies varied from >12 hours to >48 hours. The factors affecting PMV were grouped into preoperative, intraoperative and postoperative, with factors that have a high influence, including NYHA class, acute kidney injury and mediastinitis. Differences in the number of factors examined, criteria, characteristics, and time limits of the PMV used to make the study's results vary. Establishing guidelines regarding PMV time limits is essential according to current conditions.

Development and validation of prediction model for prolonged mechanical ventilation after total thoracoscopic valve replacement: a retrospective cohort study

Total thoracoscopic valve replacement (TTVR) is a minimally invasive alternative to traditional open-heart surgery. However, some patients undergoing TTVR experience prolonged mechanical ventilation (PMV). Predicting PMV risk is crucial for optimizing perioperative management and improving outcomes. We conducted a retrospective cohort study of 2,319 adult patients who underwent TTVR at a tertiary care center between January 2017 and May 2024. PMV was defined as mechanical ventilation exceeding 72 h post-surgery. A Fine-Gray competing risks regression model was developed and validated to identify predictors of PMV. Significant predictors of PMV included cardiopulmonary bypass time, ejection fraction, New York Heart Association grading, serum albumin, atelectasis, pulmonary infection, pulmonary edema, age, need for postoperative dialysis, hemoglobin levels, and PaO2/FiO2. The model demonstrated good discriminative ability, with areas under the receiver operating characteristic curves of 0.747 in the training set and 0.833 in the validation set. Calibration curves showed strong agreement between predicted and observed PMV probabilities. Decision curve analysis indicated clinical utility across a range of threshold probabilities. Our predictive model for PMV following TTVR demonstrates strong performance and clinical utility. It helps identify high-risk patients and tailor perioperative management to reduce PMV risk and improve outcomes. Further validation in diverse settings is recommended.

Minimally invasive technique facilitates early extubation after cardiac surgery: a single-center retrospective study

BACKGROUND

Postoperative time to extubation plays a role in prognosis after heart valve surgery; however, its exact impact has not been clarified. This study compared the postoperative outcomes of minimally invasive surgery and conventional sternotomy, focusing on early extubation and factors influencing prolonged mechanical ventilation.

METHODS

Data from 744 patients who underwent heart valve surgery at the Zhejiang Provincial People's Hospital between August 2019 and June 2022 were retrospectively analyzed. The outcomes in patients who underwent conventional median sternotomy (MS) and minimally invasive (MI) video-assisted thoracoscopic surgery were compared using inverse probability of treatment weighting (IPTW) and Kaplan-Meier curves. Clinical data, including surgical data, postoperative cardiac function, postoperative complications, and intensive care monitoring data, were analyzed.

RESULTS

After propensity score matching and IPTW, 196 cases of conventional MS were compared with 196 cases of MI video-assisted thoracoscopic surgery. Compared to patients in the conventional MS group, those in the MI video-assisted thoracoscopic surgery group in the matched cohort had a higher early postoperative extubation rate (P < 0.01), reduced incidence of postoperative pleural effusion (P < 0.05), significantly shorter length of stay in the intensive care unit (P < 0.01), shorter overall length of hospital stay (P < 0.01), and lower total cost of hospitalization (P < 0.01).

CONCLUSIONS

Successful early tracheal extubation is important for the intensive care management of patients after heart valve surgery. The advantages of MI video-assisted thoracoscopic surgery over conventional MS include significant reductions in the duration of use of mechanical ventilation support, reduced length of intensive care unit stay, reduced total length of hospitalization, and a favorable patient recovery rate.

Association of perioperative transfusion of fresh frozen plasma and outcomes after cardiac surgery

BACKGROUND

Fresh frozen plasma (FFP) transfusion is used to manage coagulopathy and bleeding in cardiac surgery patients despite uncertainty about its safety and effectiveness.

METHODS

We performed a propensity score matched analysis of the Australian and New Zealand Society of Cardiac and Thoracic Surgeons National Cardiac Surgery Database including patients from 39 centres from 2005 to 2018. We investigated the association of perioperative FFP transfusion with mortality and other clinical outcomes.

RESULTS

Of 119,138 eligible patients, we successfully matched 13,131 FFP recipients with 13,131 controls. FFP transfusion was associated with 30-day mortality (odds ratio (OR), 1.41; 99% CI, 1.17-1.71; p < .0001), but not with long-term mortality (hazard ratio (HR), 0.92; 99% CI, 0.85-1.00; p = .007, Holm-Bonferroni α = 0.0004). FFP was also associated with return to theatre for bleeding (OR, 1.97; 99% CI, 1.66-2.34; p < .0001), prolonged intubation (OR, 1.15; 99% CI, 1.05-1.26; p < .0001) and increased chest tube drainage (Mean difference (MD) in mL, 131; 99% CI, 120-141; p < .0001). It was also associated with reduced postoperative creatinine levels (MD in g/L, -6.33; 99% CI, -10.28 to -2.38; p < .0001).

CONCLUSION

In a multicentre, propensity score matched analysis, perioperative FFP transfusion was associated with increased 30-day mortality and had variable associations with secondary clinical outcomes.

Development and validation of a clinical prediction model for early ventilator weaning in post-cardiac surgery

Background

Weaning patients from mechanical ventilation is a critical clinical challenge post cardiac surgery. The effective liberation of patients from the ventilator significantly improves their recovery and survival rates. This study aimed to develop and validate a clinical prediction model to evaluate the likelihood of successful extubation in post-cardiac surgery patients.

Method

A predictive nomogram was constructed for extubation success in individual patients, and receiver operating characteristic (ROC) and calibration curves were generated to assess its predictive capability. The superior performance of the model was confirmed using Delong's test in the ROC analysis. A decision curve analysis (DCA) was conducted to evaluate the clinical utility of the nomogram.

Results

Among 270 adults included in our study, 107 (28.84%) experienced delayed extubation. A predictive nomogram system was derived based on five identified risk factors, including the proportion of male patients, EuroSCORE II, operation time, pump time, bleeding during operation, and brain natriuretic peptide (BNP) level. Based on the predictive system, five independent predictors were used to construct a full nomogram. The area under the curve values of the nomogram were 0.880 and 0.753 for the training and validation cohorts, respectively. The DCA and clinical impact curves showed good clinical utility of this model.

Conclusion

Delayed extubation and weaning failure, common and potentially hazardous complications following cardiac surgery, vary in timing based on factors such as sex, EuroSCORE II, pump duration, bleeding, and postoperative BNP reduction. The nomogram developed and validated in this study can accurately predict when extubation should occur in these patients. This tool is vital for assessing risks on an individual basis and making well-informed clinical decisions.

Development and Validation of Scores to Predict Prolonged Mechanical Ventilation after Cardiac Surgery

OBJECTIVES

To optimize the early prediction of prolonged postoperative mechanical ventilation after cardiac surgery (>24 hours postoperatively).

DESIGN

The authors performed a retrospective analysis.

SETTING

The Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) database was utilized.

PARTICIPANTS

All patients included in the ANZSCTS database between January 2015 and December 2018 were analyzed.

INTERVENTIONS

No interventions were performed in this observational study.

MEASUREMENTS AND MAIN RESULTS

A previously developed model was modified to allow retrospective risk calculation and model assessment (Modified Hessels score). The database was split into development and validation sets. A new risk model was developed using forward and backward stepwise elimination (ANZ-PreVent score). The authors assessed 48,382 patients, of whom 5004 (10.3%) were ventilated mechanically for >24 hours post-operatively. The Modified Hessels score demonstrated good performance in this database, with a c-index of 0.78 (95% CI 0.77-0.78) and a Brier score of 0.08. The newly developed ANZ-PreVent score demonstrated better performance (validation cohort, n = 12,229), with a c-index of 0.84 (95% CI 0.83-0.85) (p < 0.0001) and a Brier score of 0.07. Both scores performed better than the severity of illness scores commonly used to predict outcomes in intensive care.

CONCLUSIONS

The authors validated a modified version of an existing prediction score and developed the ANZ-PreVent score, with improved performance for identifying patients at risk of ventilation for >24 hours. The improved score can be used to identify high-risk patients for targeted interventions in future randomized controlled trials.

A novel nomogram for predicting the decision to delayed extubation after thoracoscopic lung cancer surgery

OBJECTIVE

Delayed extubation was commonly associated with increased adverse outcomes. This study aimed to explore the incidence and predictors and to construct a nomogram for delayed extubation after thoracoscopic lung cancer surgery.

METHODS

We reviewed medical records of 8716 consecutive patients undergoing this surgical treatment from January 2016 to December 2017. Using potential predictors to develop a nomogram and using a bootstrap-resampling approach to conduct internal validation. For external validation, we additionally pooled 3676 consecutive patients who underwent this procedure between January 2018 and June 2018. Extubation performed outside the operating room was defined as delayed extubation.

RESULTS

The rate of delayed extubation was 1.60%. Multivariate analysis identified age, BMI, FEV₁/FVC, lymph nodes calcification, thoracic paravertebral blockade (TPVB) usage, intraoperative transfusion, operative time and operation later than 6 p.m. as independent predictors for delayed extubation. Using these eight candidates to develop a nomogram, with a concordance statistic (C-statistic) value of 0.798 and good calibration. After internal validation, similarly good calibration and discrimination (C-statistic, 0.789; 95%CI, 0.748 to 0.830) were observed. The decision curve analysis (DCA) indicated the positive net benefit with the threshold risk range of 0 to 30%. Goodness-of-fit test and discrimination in the external validation were 0.113 and 0.785, respectively.

CONCLUSION

The proposed nomogram can reliably identify patients at high risk for the decision to delayed extubation after thoracoscopic lung cancer surgery. Optimizing four modifiable factors including BMI, FEV₁/FVC, TPVB usage, and operation later than 6 p.m. may reduce the risk of delayed extubation.Key Messages:This study identified eight independent predictors for delayed extubation, among which lymph node calcification and anaesthesia type were not commonly reported.Using these eight candidates to develop a nomogram, we could reliably identify high-risk patients for the decision to delayed extubation.Optimizing four modifiable factors, including BMI, FEV₁/FVC, TPVB usage, and operation later than 6 p.m. may reduce the risk of delayed extubation.

Establishment of a nomogram for predicting prolonged mechanical ventilation in cardiovascular surgery patients

AIMS

This study aimed to develop a nomogram model for predicting prolonged mechanical ventilation (PMV) in patients undergoing cardiovascular surgery.

METHODS AND RESULTS

In total, 693 patients undergoing cardiovascular surgery at an Affiliated Hospital of Nantong University between January 2018 and June 2020 were studied. Postoperative PMV was required in 147 patients (21.2%). Logistic regression analysis showed that delirium [odds ratio (OR), 3.063; 95% confidence interval (CI), 1.991-4.713; P < 0.001], intraoperative blood transfusion (OR, 2.489; 95% CI, 1.565-3.960; P < 0.001), obesity (OR, 2.789; 95% CI, 1.543-5.040; P = 0.001), postoperative serum creatinine level (mmol/L; OR, 1.012; 95% CI, 1.007-1.017; P < 0.001), postoperative serum albumin level (g/L; OR, 0.937; 95% CI, 0.902-0.973; P = 0.001), and postoperative total bilirubin level (μmol/L; OR, 1.020; 95% CI, 1.005-1.034; P = 0.008) were independent risk factors for PMV. The area under the receiver operating characteristic curve for our nomogram was found to be 0.770 (95% CI, 0.727-0.813). The goodness-of-fit test indicated that the model fitted the data well (χ2 = 12.480, P = 0.131). After the model was internally validated, the calibration plot demonstrated good performance of the nomogram, as supported by the Harrell concordance index of 0.760. Decision curve analysis demonstrated that the nomogram was clinically useful in identifying patients at risk for PMV.

CONCLUSION

We established a new nomogram model that may provide an individual prediction of PMV. This model may provide nurses, social workers, physicians, and administrators with an accurate and objective assessment tool to identify patients at high risk for PMV after cardiovascular surgery.

Three Logistic Predictive Models for the Prediction of Mortality and Major Pulmonary Complications after Cardiac Surgery

Background and Objectives: Pulmonary complications are a leading cause of morbidity after cardiac surgery. The aim of this study was to develop models to predict postoperative lung dysfunction and mortality. Materials and Methods: This was a single-center, observational, retrospective study. We retrospectively analyzed the data of 11,285 adult patients who underwent all types of cardiac surgery from 2003 to 2015. We developed logistic predictive models for in-hospital mortality, postoperative pulmonary complications occurring in the intensive care unit, and postoperative non-invasive mechanical ventilation when clinically indicated. Results: In the "preoperative model" predictors for mortality were advanced age (p < 0.001), New York Heart Association (NYHA) class (p < 0.001) and emergent surgery (p = 0.036); predictors for non-invasive mechanical ventilation were advanced age (p < 0.001), low ejection fraction (p = 0.023), higher body mass index (p < 0.001) and preoperative renal failure (p = 0.043); predictors for postoperative pulmonary complications were preoperative chronic obstructive pulmonary disease (p = 0.007), preoperative kidney injury (p < 0.001) and NYHA class (p = 0.033). In the "surgery model" predictors for mortality were intraoperative inotropes (p = 0.003) and intraoperative intra-aortic balloon pump (p < 0.001), which also predicted the incidence of postoperative pulmonary complications. There were no specific variables in the surgery model predicting the use of non-invasive mechanical ventilation. In the "intensive care unit model", predictors for mortality were postoperative kidney injury (p < 0.001), tracheostomy (p < 0.001), inotropes (p = 0.029) and PaO2/FiO2 ratio at discharge (p = 0.028); predictors for non-invasive mechanical ventilation were kidney injury (p < 0.001), inotropes (p < 0.001), blood transfusions (p < 0.001) and PaO2/FiO2 ratio at the discharge (p < 0.001). Conclusions: In this retrospective study, we identified the preoperative, intraoperative and postoperative characteristics associated with mortality and complications following cardiac surgery.

Effects of penehyclidine hydrochloride combined with dexmedetomidine on pulmonary function in patients undergoing heart valve surgery: a double-blind, randomized trial

AIM

To investigate the effects of penehyclidine hydrochloride combined with dexmedetomidine on pulmonary function in patients undergoing heart valve surgery with cardiopulmonary bypass (CPB).

METHODS

A total of 180 patients undergoing elective heart valve surgery with CPB were randomly divided into four groups: 45 in group P (intravenous penehyclidine hydrochloride 0.02 mg/kg 10 min before anesthesia induction and at the beginning of CPB, total 0.04 mg/kg); 43 in group D (dexmedetomidine 0.5 μg/kg/h after induction of anesthesia until the end of anesthesia); 44 in group PD ( penehyclidine hydrochloride 0.04 mg/kg combined with dexmedetomidine 0.5 μg/kg/h intravenously during anesthesia); and 43 in group C (same amount of normal saline 10 min before and after anesthesia induction, to the end of anesthesia, and at the beginning of CPB). The main outcomes were the incidence and severity of postoperative pulmonary complications (PPCs). The secondary outcomes were: (1) extubation time, length of stay in intensive care, and postoperative hospital stay, and adverse events; and (2) pulmonary function evaluation indices (oxygenation index and respiratory index) and plasma inflammatory factor concentrations (tumor necrosis factor-α, interleukin-6, C-reactive protein and procalcitonin) during the perioperative period.

RESULTS

The incidence of PPCs in groups P, D and PD after CPB was lower than that in group C (P < 0.05), and the incidence in group PD was significantly lower than that in groups P and D (P < 0.05). The scores for PPCs in groups P, D and PD were lower than those in group C (P < 0.05).

CONCLUSION

Combined use of penehyclidine hydrochloride and dexmedetomidine during anesthesia reduced the occurrence of postoperative pulmonary dysfunction, and improved the prognosis of patients undergoing heart valve surgery with CPB.

TRIAL REGISTRATION

The trial was registered in the Chinese Clinical Trial Registry on 3/11/2020 (Registration No.: ChiCTR2000039610).

A simple-to-use nomogram for predicting prolonged mechanical ventilation for children after Ebstein anomaly corrective surgery: a retrospective cohort study

BACKGROUND

Prolonged mechanical ventilation (PMV) after pediatric cardiac surgery imposes a great burden on patients in terms of morbidity, mortality as well as financial costs. Ebstein anomaly (EA) is a rare congenital heart disease, and few studies have been conducted about PMV in this condition. This study aimed to establish a simple-to-use nomogram to predict the risk of PMV for EA children.

METHODS

The retrospective study included patients under 18 years who underwent corrective surgeries for EA from January 2009 to November 2021. PMV was defined as postoperative mechanical ventilation time longer than 24 hours. Through multivariable logistic regression, we identified and integrated the risk factors to develop a simple-to-use nomogram of PMV for EA children and internally validated it by bootstrapping. The calibration and discriminative ability of the nomogram were determined by calibration curve, Hosmer-Lemeshow goodness-of-fit test and receiver operating characteristic (ROC) curve.

RESULTS

Two hundred seventeen children were included in our study of which 44 (20.3%) were in the PMV group. After multivariable regression, we obtained five risk factors of PMV. The odds ratios and 95% confidence intervals (CI) were as follows: preoperative blood oxygen saturation, 0.876(0.805,0.953); cardiothoracic ratio, 3.007(1.107,8.169); Carpentier type, 4.644(2.065,10.445); cardiopulmonary bypass time, 1.014(1.005,1.023) and postoperative central venous pressure, 1.166(1.016,1.339). We integrated the five risk factors into a nomogram to predict the risk of PMV. The area under ROC curve of nomogram was 0.805 (95% CI, 0.725,0.885) and it also provided a good discriminative information with the corresponding Hosmer-Lemeshow p values > 0.05.

CONCLUSIONS

We developed a nomogram by integrating five independent risk factors. The nomogram is a practical tool to early identify children at high-risk for PMV after EA corrective surgery.

SPECKLE TRACKING QUANTIFICATION PARASTERNAL INTERCOSTAL MUSCLE LONGITUDINAL STRAIN TO PREDICT WEANING OUTCOMES: A MULTICENTRIC OBSERVATIONAL STUDY

ABSTRACT

Background: The purpose of this study was to determine the feasibility, reliability, and reproducibility of parasternal intercostal muscle longitudinal strain (LSim) quantification by speckle tracking and the value of maximal LSim to predict weaning outcomes. Methods: This study was divided into three phases. Phases 1 and 2 comprehended prospective observational programs to evaluate the feasibility, reliability, and repeatability of speckle tracking to assess LSim in healthy subjects and mechanically ventilated patients. Phase 3 was a multicenter retrospective study to evaluate the value of maximal LSim, intercostal muscle thickening fraction (TFim), diaphragmatic thickening fraction, diaphragmatic excursion, and rapid shallow breathing index to predict weaning outcomes. Results: A total of 25 healthy subjects and 20 mechanically ventilated patients were enrolled in phases 1 and 2, respectively. Maximal LSim was easily accessible, and the intraoperator reliability and interoperator reliability were excellent in eupnea, deep breathing, and mechanical ventilation. The intraclass correlation coefficient ranged from 0.85 to 0.96. Moreover, 83 patients were included in phase 3. The areas under the receiver operating characteristic curve of maximal LSim, TFim, diaphragmatic thickening fraction, diaphragmatic excursion, and rapid shallow breathing index were 0.91, 0.79, 0.71, 0.70, and 0.78 for the prediction of successful weaning, respectively. The best cutoff values of LSim and TFim were >-6% (sensitivity, 100%; specificity, 64.71%) and <7.6% (sensitivity, 100%; specificity, 50.98%), respectively. Conclusions: The quantification of LSim by speckle tracking was easily achievable in healthy subjects and mechanically ventilated patients and presented a higher predictive value for weaning success compared with conventional weaning parameters. Trial registration no. ChiCTR2100049817.

Comparison of assessment of diaphragm function using speckle tracking between patients with successful and failed weaning: a multicentre, observational, pilot study

Background

Diaphragmatic ultrasound has been increasingly used to evaluate diaphragm function. However, current diaphragmatic ultrasound parameters provide indirect estimates of diaphragmatic contractile function, and the predictive value is controversial. Two-dimensional (2D) speckle tracking is an effective technology for measuring tissue deformation and can be used to measure diaphragm longitudinal strain (DLS) to assess diaphragm function. The purpose of this study was to determine the feasibility and reproducibility of DLS quantification by 2D speckle tracking and to determine whether maximal DLS could be used to predict weaning outcomes.

Methods

This study was performed in the intensive care unit of two teaching hospitals, and was divided into two studies. Study A was a prospective study to evaluate the feasibility, reliability, and repeatability of speckle tracking in assessing DLS in healthy subjects and mechanically ventilated patients. Study B was a multicentre retrospective study to assess the use of maximal DLS measured by speckle tracking in predicting weaning outcomes.

Results

Twenty-five healthy subjects and twenty mechanically ventilated patients were enrolled in Study A. Diaphragmatic speckle tracking was easily accessible. The intra- and interoperator reliability were good to excellent under conditions of eupnoea, deep breathing, and mechanical ventilation. The intraclass correlation coefficient (ICC) ranged from 0.78 to 0.95. Ninety-six patients (fifty-nine patients were successfully weaned) were included in Study B. DLS exhibited a fair linear relationship with both the diaphragmatic thickening fraction (DTF) (R2 = 0.73, p < 0.0001) and diaphragmatic excursion (DE) (R2 = 0.61, p < 0.0001). For the prediction of successful weaning, the areas under the ROC curves of DLS, diaphragmatic thickening fraction DTF, RSBI, and DE were 0.794, 0.794, 0.723, and 0.728, respectively. The best cut-off value for predicting the weaning success of DLS was less than -21%, which had the highest sensitivity of 89.19% and specificity of 64.41%.

Conclusions

Diaphragmatic strain quantification using speckle tracking is easy to obtain in healthy subjects and mechanically ventilated patients and has a high predictive value for mechanical weaning. However, this method offers no advantage over RSBI. Future research should assess its value as a predictor of weaning.

Trial registration

This study was registered in the Chinese Clinical Trial Register (ChiCTR), ChiCTR2100049816. Registered 10 August 2021. http://www.chictr.org.cn/showproj.aspx?proj=131790

Clinical Evaluation of on-Table Extubation in Patients Aged Over 60 Years Undergoing Minimally Invasive Mitral or Aortic Valve Replacement Surgery

Aims

To evaluate the clinical efficiency of on-table extubation (OTE) versus delayed extubation in patients aged over 60 years that underwent minimally invasive mitral or aortic valve replacement surgery and evaluate the factors associated with successful OTE implementation.

Materials

Patients over 60 years with mitral or aortic valve disease who received minimally invasive mitral or aortic valve replacement surgery from October 2020 to October 2021 were selected retrospectively. We divided patients into the on-table extubated (OTE) group (n = 71) and the delayed extubation (DE) group (n = 22). Preoperative, intraoperative, and postoperative clinical variables were compared between the two groups.

Results

Patients in the DE group underwent longer surgery time, longer aortic occlusion clamping time and longer cardiopulmonary bypass time than those in the OTE group(217.48 ± 27.83 vs 275.91 ± 77.22, p = 0.002; 76.49 ± 16.00 vs 126.55 ± 54.85, p = 0.001; 112.87 ± 18.91 vs 160.77 ± 52.17, p = 0.001). Patients in the OTE group had shorter postoperative mechanical ventilation time (min), shorter ICU time, shorter postoperative hospital length of stay and lower total cost and medication cost (p < 0.05). The AUC for aortic occlusion clamping time was 0.81 (p < 0.01), making it the most significant predictor of on-table extubation success.

Conclusions

On-table extubation following mitral or aortic valve cardiac surgery was associated with a superior clinical outcome and high cost-effectiveness.

Lung failure after polytrauma with concomitant thoracic trauma in the elderly: an analysis from the TraumaRegister DGU®

Background

In developed countries worldwide, the number of older patients is increasing. Pulmonary complications are common in multiple injured patients with chest injuries. We assessed whether geriatric patients develop lung failure following multiple trauma with concomitant thoracic trauma more often than younger patients.

Methods

A retrospective analysis of severely injured patients with concomitant blunt thoracic trauma registered in the TraumaRegister DGU® (TR-DGU) between 2009 and 2018 was performed. Patients were categorized into four age groups: 55–64 y, 65–74 y, 75–84 y, and ≥ 85 y. Adult patients aged 18–54 years served as a reference group. Lung failure was defined as PaO2/FIO2 ≤ 200 mm Hg, if mechanical ventilation was performed.

Results

A total of 43,289 patients were included, of whom 9238 (21.3%) developed lung failure during their clinical stay. The rate of posttraumatic lung failure was seen to increase with age. While lung failure markedly increased the length of hospital stay, duration of mechanical ventilation, and length of ICU stay independent of the patient’s age, differences between younger and older patients with lung failure in regard to these parameters were clinically comparable. In addition, the development of respiratory failure showed a distinct increase in mortality with higher age, from 16.9% (18–54 y) to 67.2% (≥ 85 y).

Conclusion

Development of lung failure in severely injured patients with thoracic trauma markedly increases hospital length of stay, length of ICU stay, and duration of mechanical ventilation in patients, regardless of age. The development of respiratory failure appears to be related to the severity of the chest trauma rather than to increasing patient age. However, the greatest effects of lung failure, particularly in terms of mortality, were observed in the oldest patients.

A Predictive Scoring Model for Postoperative Tracheostomy in Patients Who Underwent Cardiac Surgery

Background

A subset of patients require a tracheostomy as respiratory support in a severe state after cardiac surgery. There are limited data to assess the predictors for requiring postoperative tracheostomy (POT) in cardiac surgical patients.

Methods

The records of adult patients who underwent cardiac surgery from 2016 to 2019 at our institution were reviewed. Univariable analysis was used to assess the possible risk factors for POT. Then multivariable logistic regression analysis was performed to identify independent predictors. A predictive scoring model was established with predictor assigned scores derived from each regression coefficient divided by the smallest one. The area under the receiver operating characteristic curve and the Hosmer-Lemeshow goodness-of-fit test were used to evaluate the discrimination and calibration of the risk score, respectively.

Results

A total of 5,323 cardiac surgical patients were included, with 128 (2.4%) patients treated with tracheostomy after cardiac surgery. Patients with POT had a higher frequency of readmission to the intensive care unit (ICU), longer stay, and higher mortality (p &lt; 0.001). Mixed valve surgery and coronary artery bypass grafting (CABG), aortic surgery, renal insufficiency, diabetes mellitus, chronic obstructive pulmonary disease (COPD), pulmonary edema, age &gt;60 years, and emergent surgery were independent predictors. A 9-point risk score was generated based on the multivariable model, showing good discrimination [the concordance index (c-index): 0.837] and was well-calibrated.

Conclusions

We established and verified a predictive scoring model for POT in patients who underwent cardiac surgery. The scoring model was conducive to risk stratification and may provide meaningful information for clinical decision-making.

Preoperative Thoracic CT Findings Associated With Postoperative Mechanical Ventilation in Patients Undergoing Major Abdominal or Pelvic Surgery: A Matched Case-Control Study

Background: Postoperative prolonged mechanical ventilation is associated with increased morbidity and mortality. Reliable predictors of postoperative mechanical ventilation after abdominal or pelvic surgeries are lacking. Objective: To explore associations between preoperative thoracic CT findings and need for postoperative mechanical ventilation after major abdominal or pelvic surgeries. Methods: This retrospective case-control study included patients who underwent abdominal or pelvic surgeries (01/01/2014-12/31/2018) and underwent preoperative thoracic CT. Cases were patients who required postoperative mechanical ventilation. Control and case patients were matched at a 3:1 ratio based on age, sex, body mass index, chronic obstructive pulmonary disease, smoking status, and surgery type. Two radiologists (R1, R2) reviewed CT images. Findings were compared between groups. Results: The study included 165 patients (70 female, 95 male; mean age 67.0±9.7 years; 42 cases, 123 matched controls). Bronchial wall thickening and pericardial effusion were more frequent in cases than controls for R2 (10% vs 2%, p=.03; 17% vs 5%, p=.01), but not R1. Pulmonary artery diameter was greater in cases than controls for R2 (2.9±0.5 cm vs 2.8±0.5 cm, p=.045) but not R1. Right lung height was lower in cases than controls for R1 (18.4±2.9 cm vs 19.9±2.7 cm, p=.01) and R2 (18.3±2.9 cm vs 19.8±2.7 cm, p=.01). Left lung height was lower in cases than controls for R1 (19.5±3.1 cm vs 21.1±2.6 cm, p=.01) and R2 (19.6±2.4 cm vs 20.9±2.6 cm, p=.01). Anteroposterior chest diameter was greater for cases than controls for R1 (14.0±2.3 cm vs 12.9±3.7 cm, p=.02) and R2 (14.2±2.2 cm vs 13.2±3.6 cm, p=.04). In multivariable regression model using pooled reader data, bronchial wall thickening exhibited odds ratio (OR) of 4.6 (95% CI: 1.3, 16.5; p=.02); pericardial effusion, OR 5.1 (95% CI: 1.7, 15.5; p=.004); pulmonary artery diameter, OR 1.4 (95% CI: 0.7, 3.0; p=.32); mean lung height, OR 0.8 (95% CI: 0.7, 1.001; p=.05); anteroposterior chest diameter, OR 1.2 (95% CI: 1.013, 1.4; p=.03). Conclusion: CT features are associated with the need for postoperative mechanical ventilation following abdominal or pelvic surgery. Clinical Impact: Many patients undergo thoracic CT before abdominal or pelvic surgery; the CT findings may complement preoperative clinical risk factors.

Postoperative Changes in Pulmonary Function after Valve Surgery: Oxygenation Index Early after Cardiopulmonary Is a Predictor of Postoperative Course

Objective: To determine pulmonary functional changes that predict early clinical outcomes in valve surgery requiring long cardiopulmonary bypass (CPB). Methods: This retrospective study included 225 consecutive non-emergency valve surgeries with fast-track cardiac anesthesia between January 2014 and March 2020. Blood gas analyses before and 0, 2, 4, 8, and 14 h after CPB were investigated. Results: Median age and EuroSCORE II were 71.0 years (25–75 percentile: 59.5–77.0) and 2.46 (1.44–5.01). Patients underwent 96 aortic, 106 mitral, and 23 combined valve surgeries. The median CPB time was 151 min (122–193). PaO₂/FiO₂ and AaDO₂/PaO₂ significantly deteriorated two hours, but not immediately, after CPB (both p < 0.0001). Decreased PaO₂/FiO₂ and AaDO₂/PaO₂ were correlated with ventilation time (r² = 0.318 and 0.435) and intensive care unit (ICU) (r² = 0.172 and 0.267) and hospital stays (r² = 0.164 and 0.209). Early and delayed extubations (<6 and >24 h) were predicted by PaO₂/FiO₂ (377.2 and 213.1) and AaDO₂/PaO₂ (0.683 and 1.680), measured two hours after CPB with acceptable sensitivity and specificity (0.700–0.911 and 0.677–0.859). Conclusions: PaO₂/FiO₂ and AaDO₂/PaO₂ two hours after CPB were correlated with ventilation time and lengths of ICU and hospital stays. These parameters suitably predicted early and delayed extubations.

Development and Validation of a Predictive Score for Prolonged Mechanical Ventilation After Cardiac Surgery

OBJECTIVES

The authors aimed to identify risk factors associated with prolonged mechanical ventilation (PMV) after scheduled cardiac surgery under cardiopulmonary bypass (CPB).

DESIGN

A single-center, observational study.

SETTING

Tertiary hospital.

PARTICIPANTS

All adult patients who underwent scheduled cardiac surgery under cardiopulmonary bypass between January 2017 and December 2017.

INTERVENTIONS

None.

MEASUREMENT AND MAIN RESULTS

Among the 568 patients included, 68 (12.0%) presented a PMV. The median ventilation time was 5.7 hours in the group without PMV and 85.2 hours in the group with PMV. A logistic regression found five variables independently associated with the occurrence of PMV: (1) prior cardiac surgery, (2) preoperative congestive heart failure, (3) preoperative creatinine clearance <30 mL/min/1.73 m², (4) intraoperative implantation of extracorporeal membrane oxygenation, and (5) serum lactate >4 mmol/L on admission. A predictive score to allow the authors to anticipate PMV was developed from the regression coefficient of perioperative factors independently associated with PMV. With a threshold of 2/13, the score had a sensitivity of 80.9%, a specificity of 80.5%, a positive predictive value of 37.2%, and a negative predictive value of 96.7%. The score then was validated in a distinct cohort.

CONCLUSIONS

The study authors have developed a simple score to predict PMV in patients undergoing cardiac surgery with CPB. This score could allow clinicians to identify a high-risk population that might benefit from specific management upon arrival in the intensive care unit.

Risk factors for and outcomes of prolonged mechanical ventilation in patients received DeBakey type I aortic dissection repairment

Background

This study aimed to identify risk factors for prolonged mechanical ventilation (PMV) and its association with disease prognosis following acute DeBakey type I aortic dissection surgery.

Methods

A total of 582 patients who received emergency surgery for acute DeBakey type I aortic dissection from 2014 to 2018 were enrolled in this study. Mechanical ventilation period after surgery longer than 48 hours was defined as postoperative PMV. Multiple logistic regression analysis was used to identify risk factors for PMV. This study also compared short- and long-term outcomes in patients who developed PMV with patients who did not develop this complication. To identify and compare long-term cumulative survival rate, Kaplan-Meier survival curve was plotted.

Results

Among all enrolled patients, 259 (44.5%) received PMV treatment. Our data suggested that the length of intensive care unit and hospital stay were longer for patients who received PMV treatment. Thirty-day mortality was also higher in patients with PMV than in patients without PMV. Elevated leukocyte count and increased serum cystatin C level upon admission, lower preoperative platelet count and longer cardiopulmonary bypass (CPB) duration were identified as risk factors for PMV. Interestingly, our data suggested that there was no significant difference of survival rate between patients with or without PMV history.

Conclusions

PMV after DeBakey type I aortic dissection repair surgery was a common complication and associated with increased short-term mortality rate but did not affect long-term mortality rate. Elevated preoperative leukocyte count, increased preoperative serum cystatin C level, lower preoperative platelet count and longer CPB duration were risk factors for PMV.

Perioperative risk factors for delayed extubation after acute type A aortic dissection surgery

Background

Delayed extubation after cardiac surgery is associated with high morbidity and mortality, increased intensive care unit length of stay, and healthcare cost. Acute type A aortic dissection (ATAAD) generally results in prolonged mechanical ventilation due to the complexity of surgical management and some postoperative complications. This study aimed to elucidate the perioperative risk factors for delayed extubation in patients undergoing ATAAD surgery.

Methods

A retrospective cohort study including 239 patients who were diagnosed with ATAAD and underwent emergency surgery from October 2004 to January 2018 was performed. The potential perioperative risk factors for delayed extubation were collected. This study defined delayed extubation as the time to commence extubation being greater than 48 hours. The clinical data were analyzed with univariate and multivariate analyses to identify risk factors for delayed extubation following ATAAD surgery.

Results

The incidence of delayed extubation was 48.5% (n=116). Multiple logistic regression analysis showed perioperative risk factors for delayed extubation included preoperative cardiac tamponade [odds ratio (OR) 3.94, 95% confidence interval (CI) 1.39–11.17, P=0.010], central arterial cannulation (ascending aorta and proximal aortic arch) for cardiopulmonary bypass (CPB) (OR 4.04, 95% CI: 1.03–15.91, P=0.046), postoperative stroke (OR 10.58, 95% CI: 2.65–42.25, P=0.001), postoperative renal dysfunction that required temporary hemodialysis (OR 6.60 95% CI: 1.97–22.11, P=0.002), and re-exploration to stop bleeding (OR 2.65, 95% CI: 1.00–6.99, P=0.050).

Conclusions

Preoperative cardiac tamponade, central arterial cannulation for CPB, postoperative stroke, postoperative renal dysfunction that required temporary hemodialysis, and re-exploration to stop bleeding are perioperative risk factors for delayed extubation. Identification of the potential risk factors for delayed extubation may help optimize the perioperative management and improve postoperative outcomes of patients undergoing ATAAD surgery.

Predictors and outcomes of postoperative respiratory failure after cardiac surgery

BACKGROUND

Postoperative respiratory failure after cardiac surgery (CS-PRF) is a devastating complication and its incidence and predictors vary depending on how it is defined and the patient population.

AIMS

This study was conducted to determine the incidence, predictors and outcomes of CS-PRF defined as prolonged mechanical ventilation >48 hours and reintubation.

METHODS

This is a retrospective chart review of 1257 patients who underwent cardiac surgery between June 2011 and December 2018. The research questions were addressed through bivariate inferential, descriptive and binary logistic regression.

RESULTS

The overall incidence of CS-PRF was 15.9% and significant regression predictors included diabetes mellitus (OR = 1.77, P = .001), preoperative renal replacement therapy (OR = 2.07, P = .033), need for intraoperative transfusion (OR = 2.35, P = .000), combined coronary bypass/valvular surgery (OR = 2.61, P = .001) and intra-aortic balloon pump (OR = 3.60, P = .000). CS-PRF patients had increased postoperative blood transfusions (69.5% vs 27.9%, P = .000), reoperation for bleeding (9.0 vs 0.4%, P = .000), pleural effusion (13.5% vs 4.1%, P = .000), pneumonia (33.5% vs 1.6%, P = .000), acute kidney injury (70.9% vs 39.9%, P = .000), atrial fibrillation (42.5% vs 26.3%, P = .000), coma/encephalopathy (21.5% vs 3.3%, P = .000) and cerebrovascular accident (6.0% vs 1.3%, P = .000). They also had longer intensive care (262.1 vs 97.4 hours, P = .000) and hospital lengths of stay (17 vs 8 days, P = .000), and increased in-hospital mortality (17.5% vs 0.4%, P = .000). Survivors of CS-PRF were less likely to be discharged home (38.0% vs 84.4%, P = .000).

CONCLUSIONS

Knowledge of predictors for CS-PRF may help identify patients who are at risk for this complication and who may benefit from preventive measures to promote early extubation and to avert reintubation.

Early extubation in current valve surgery requiring long cardiopulmonary bypass: Benefits and predictive value of preoperative spirometry

BACKGROUND

Early extubation (EEx) after cardiac surgery has been essentially studied in patients with short cardiopulmonary bypass (CPB). Whether preoperative spirometry can predict EEx remains controversial.

OBJECTIVES

To investigate whether EEx can be a goal and predicted by preoperative spirometry in valve surgery requiring long CPB.

METHODS

Nonemergent consecutive 210 patients who underwent valve surgery from January 2014 to August 2019 were investigated retrospectively.

RESULTS

EEx (<8 h) was achieved in 93 (44.3%) patients without increasing adverse events. Patients with EEx had shorter ICU and hospital stays than those without EEx. Multivariate analysis showed that higher estimated glomerular filtration rate and mitral valve repair were significant protective factors for EEx. Conversely, moderate and severe chronic obstructive pulmonary disease defined by spirometry, longer operation, CPB, and aortic cross-clamp time were significant risk factors.

CONCLUSIONS

EEx should be the goal in current valve surgery. Preoperative spirometry is a significant predictor.

Risk Factors for Delayed Extubation Following High Posterior Cervical and Occipital Fusion

BACKGROUND

Much has been written on initial airway management in patients undergoing cervical spine procedures, but comparatively less is known about extubation criteria. High cervical and occipital fusion procedures pose a particular risk for extubation given the potential for a reduced range of motion at the occiput-C1 and C1-C2 joints should reintubation be necessary.

MATERIALS AND METHODS

We performed a retrospective cohort analysis of posterior high cervical and occipital fusion cases to identify factors related to delayed extubation and postoperative airway and pulmonary complications. Using a convenience sample of all cases operated between January 2009 and April 2018, we reviewed anesthesia records and discharge summaries to compare patient characteristics, airway management, surgical factors, and postoperative complications between patients who underwent delayed extubation and those who did not.

RESULTS

A total of 135 patients met our inclusion criteria. Overall, 92 (68.1%) patients were extubated in the operating room (OR), and 43 (31.9%) underwent delayed extubation. Multivariate logistic regression analysis identified age, procedure length, C2 as the highest level fused, and percentage colloid administered as predictors of delayed extubation. We did not find a difference in the rate of postoperative pulmonary complications between groups (6/92 [6.5%] for OR extubation; 2/43 [4.7%] for delayed extubation). Two patients had serious airway complications, and both were extubated in the OR (2/92, 2.2%).

CONCLUSIONS

The decision to extubate immediately postoperatively after high cervical and occipital fusion should be considered carefully as the morbidity associated with airway obstruction can be severe in this population, while negative effects of delayed extubation were not evident in our analysis.

Evaluation of two intensive care models in relation to successful extubation after cardiac surgery

OBJECTIVE

To compare outcomes between intensivist-directed and cardiac surgeon-directed care delivery models.

DESIGN

This retrospective, historical-control study was performed in a cohort of adult cardiac surgical patients at Zhongshan Hospital (Fudan University, China). During the first phase (March to August 2015), cardiac surgeons were in charge of postoperative care while intensivists were in charge during the second phase (September 2015-June 2016). Both phases were compared regarding successful extubation rate, intensive care unit (ICU) length of stay (LOS), and in-hospital mortality.

SETTING

Tertiary Zhongshan Hospital (Fudan University, China).

PATIENTS

Consecutive adult patients admitted to the cardiac surgical ICU (CSICU) after heart surgery.

INTERVENTIONS

Phase I patients treated by cardiac surgeons, and phase II patients treated by intensivists.

MAIN VARIABLES OF INTEREST

Successful extubation, ICU LOS and in-hospital mortality.

RESULTS

A total of 1792 (phase I) and 3007 patients (phase II) were enrolled. Most variables did not differ significantly between the two phases. However, patients in phase II had a higher successful extubation rate (99.17% vs. 98.55%; p=0.043) and a shorter median duration of mechanical ventilation (MV) (18 vs. 19h; p<0.001). In relation to patients with MV duration >48h, those in phase II had a comparatively higher successful extubation rate (p=0.033), shorter ICU LOS (p=0.038) and a significant decrease in in-hospital mortality (p=0.039).

CONCLUSIONS

The intensivist-directed care model showed improved rates of successful extubation and shorter MV durations after cardiac surgery.

The Effects of Escalation of Respiratory Support and Prolonged Invasive Ventilation on Outcomes of Cardiac Surgical Patients: A Retrospective Cohort Study

Objectives

The aim of this study was to determine the effects of escalation of respiratory support and prolonged postoperative invasive ventilation on patient-centered outcomes, and identify perioperative factors associated with these 2 respiratory complications.

Design

A retrospective cohort analysis of cardiac surgical patients admitted to the cardiothoracic intensive care unit (ICU) between August 2015 and January 2018. Escalation of respiratory support was defined as “unplanned continuous positive airway pressure,” “non-invasive ventilation,” or “reintubation” after surgery; prolonged invasive ventilation was defined as “invasive ventilation beyond the first 12 hours following surgery.” The primary endpoint was the composite of escalation of respiratory support and prolonged ventilation.

Setting

Tertiary cardiothoracic ICU.

Participants

A total of 2,098 patients were included and analyzed.

Interventions

None.

Measurements and Main Results

The composite of escalation of support or prolonged ventilation occurred in 509 patients (24.3%). Patients who met the composite had higher mortality (2.9% v 0.1%; p < 0.001) and longer median [interquartile range] length of ICU (2.1 [1.0-4.9] v 0.9 [0.8-1.0] days; p < 0.0001) and hospital (10.6 [8.0-16.0] v 7.2 [6.2-10.0] days; p < 0.0001) stay. Hypoxemia and anemia on admission to ICU were the only 2 factors independently associated with the need for escalation of respiratory support or prolonged invasive ventilation.

Conclusions

Escalation of respiratory support or prolonged invasive ventilation is frequently seen in cardiac surgery patients and is highly associated with increased mortality and morbidity. Hypoxemia and anemia on admission to the ICU are potentially modifiable factors associated with escalation of respiratory support or prolonged invasive ventilation.

Balancing intubation time with postoperative risk in cardiac surgery patients - a retrospective cohort analysis

Introduction

Intubation time in patients undergoing cardiac surgery may be associated with increased mortality and morbidity. Premature extubation can have serious adverse physiological consequences. The aim of this study was to determine the influence of intubation time on morbidity and mortality in patients undergoing cardiac surgery.

Methods

We performed a retrospective analysis of data on 1,904 patients undergoing isolated coronary artery bypass grafting (CABG) and stratified them by duration of intubation time after surgery - 0-6, 6-9, 9-12, 12-24 and over 24 hours. Postoperative complications risk analysis was performed using multivariate logistic regression analysis for patients extubated ≤12 and >12 hours.

Results

Intubation percentages in each time cohort were as follows: 0-6 hours - 7.8%, 6-9 hours - 17.3%, 9-12 hours - 26.8%, 12-24 hours - 44.4% and >24 hours - 3.7%. Patients extubated ≤12 hours after CABG were younger, mostly males, more often smokers, with lower preoperative risk. They had lower 30-day mortality (2.02% vs 4.59%, P=0.002), shorter hospital stay (7.68±4.49 vs 9.65±12.63 days, P<0.001) and shorter intensive care unit stay (2.39 vs 3.30 days, P<0.001). Multivariate analysis showed that intubation exceeding 12 hours after CABG increases the risk of postoperative delirium (OR 1.548, 95% CI 1.161-2.064, P=0.003) and risk of postoperative hemofiltration (OR 1.302, 95% CI 1.023-1.657, P=0.032).

Conclusion

Results indicate that risk of postoperative complications does not increase until intubation time exceeds 12 hours. Shorter intubation time is seen in younger, men and smokers. Intubation time >12 hours is a risk factor for postoperative delirium and hemofiltration after cardiac surgery.

Chronic critical illness: are we saving patients or creating victims?

The technological advancements that allow support for organ dysfunction have led to an increase in survival rates for the most critically ill patients. Some of these patients survive the initial acute critical condition but continue to suffer from organ dysfunction and remain in an inflammatory state for long periods of time. This group of critically ill patients has been described since the 1980s and has had different diagnostic criteria over the years. These patients are known to have lengthy hospital stays, undergo significant alterations in muscle and bone metabolism, show immunodeficiency, consume substantial health resources, have reduced functional and cognitive capacity after discharge, create a sizable workload for caregivers, and present high long-term mortality rates. The aim of this review is to report on the most current evidence in terms of the definition, pathophysiology, clinical manifestations, treatment, and prognosis of persistent critical illness.

The use of Rapid Shallow Breathing Index shortens time to extubation in patients undergoing coronary artery bypass grafting

Background

This study aims to investigate the effects of the use of the Rapid Shallow Breathing Index on extubation success and time to extubation in patients undergoing elective isolated coronary artery bypass grafting.

Methods

This prospective, randomized-controlled study included a total of 72 patients (55 males, 19 females; mean age 60.3±9.3 years; range 45 to 76 years) who underwent isolated coronary artery bypass grafting between February 2016 and November 2016. The patients were divided into two groups as the RSBI group (n=36) and the control group (n=36). The control group was extubated by conventional criteria that were routinely applied in our clinic, while the RSBI group was extubated, when the index scores became below 77 breaths per min/L, following ensuring hemodynamic stability and weaning procedure from mechanical ventilation.

Results

The mean time to wean from mechanical ventilation was 5.8±1.0 hours in the RSBI group and 8.1±2.0 hours in the control group (p=0.03). Extubation protocol performed through the use of the index was found to provide 26% earlier extubation compared to the conventional extubation criteria. There was no significant difference in the postoperative follow-up parameters or clinical conditions.

Conclusion

Our study results show that a practical tool such as the Rapid Shallow Breathing Index can be reliably used for making a decision in favor of extubation in patients undergoing coronary artery bypass grafting. A shortened time to extubation by the use of this index may provide substantial benefits in terms of prevention of infections, mechanical ventilation-induced lung injuries, and potential pulmonary complications.

Pulmonary Perfusion and Ventilation during Cardiopulmonary Bypass Are Not Associated with Improved Postoperative Outcomes after Cardiac Surgery

OBJECTIVES

Clinical trials of either pulmonary perfusion or ventilation during cardiopulmonary bypass (CBP) are equivocal. We hypothesized that to achieve significant improvement in outcomes both interventions had to be concurrent.

DESIGN

Retrospective case-control study.

SETTINGS

Major academic tertiary referral medical center.

PARTICIPANTS

Two hundred seventy-four consecutive patients who underwent open heart surgery with CBP 2009-2013.

INTERVENTIONS

The outcomes of 86 patients who received pulmonary perfusion and ventilation during CBP were retrospectively compared to the control group of 188 patients.

MEASUREMENTS AND MAIN RESULTS

Respiratory complications rates were similar in both groups (33.7 vs. 33.5%), as were the rates of postoperative pneumonia (4.7 vs. 4.3%), pleural effusions (13.9 vs. 12.2%), and re-intubations (9.3 vs. 9.1%). Rates of adverse postoperative cardiac events including ventricular tachycardia (9.3 vs. 8.5%) and atrial fibrillation (33.7 vs. 28.2%) were equivalent in both groups. Incidence of sepsis (8.1 vs. 5.3%), postoperative stroke (2.3 vs. 2.1%), acute kidney injury (2.3 vs. 3.7%), and renal failure (5.8 vs. 3.7%) was likewise comparable. Despite similar transfusion requirements, coagulopathy (12.8 vs. 5.3%, p = 0.031) and the need for mediastinal re-exploration (17.4 vs. 9.6%, p = 0.0633) were observed more frequently in the pulmonary perfusion and ventilation group, but the difference did not reach the statistical significance. Intensive care unit (ICU) and hospital stays, and the ICU readmission rates (7.0 vs. 8.0%) were similar in both groups.

CONCLUSION

Simultaneous pulmonary perfusion and ventilation during CBP were not associated with improved clinical outcomes.

Elevated Red Cell Distribution Width Is Associated With Decreased Ventilator-Free Days in Critically Ill Patients

INTRODUCTION

Elevated red cell distribution width (RDW) is associated with mortality in a variety of respiratory conditions. Recent data also suggest that RDW is associated with mortality in intensive care unit (ICU) patients. Although respiratory failure is common in the ICU, the relationship between RDW and pulmonary outcomes in the ICU has not been previously explored. Therefore, our goal was to investigate the association of admission RDW with 30-day ventilator-free days (VFDs) in ICU patients.

METHODS

We performed a retrospective analysis from an ongoing prospective, observational study. Patients were recruited from medical and surgical ICUs of a large teaching hospital in Boston, Massachusetts. The RDW was assessed within 1 hour of ICU admission. Poisson regression analysis was used to investigate the association of RDW (normal: 11.5%-14.5% vs elevated: >14.5%) with 30-day VFD, while controlling for age, sex, race, body mass index, Nutrition Risk in the Critically Ill score, the presence of chronic lung disease, Pao₂/Fio₂ ratio, and admission levels of hemoglobin, mean corpuscular volume, phosphate, albumin, C-reactive protein, and creatinine.

RESULTS

A total of 637 patients comprised the analytic cohort. Mean RDW was 15 (standard deviation 4%), with 53% of patients in the normal range and 47% with elevated levels. Median VFD was 16 (interquartile range: 6-25) days. Poisson regression analysis demonstrated that ICU patients with elevated admission RDW were likely to have 32% lower 30-day VFDs compared to their counterparts with RDW in the normal range (incidence rate ratio: 0.68; 95% confidence interval: 0.55-0.83: P < .001).

CONCLUSIONS

We observed an inverse association of RDW and 30-day VFD, despite controlling for demographics, nutritional factors, and severity of illness. This supports the need for future studies to validate our findings, understand the physiologic processes that lead to elevated RDW in patients with respiratory failure, and determine whether changes in RDW may be used to support clinical decision-making.

Preoperative maximal expiratory pressure is associated with duration of invasive mechanical ventilation after cardiac surgery: An observational study

OBJECTIVE

To evaluate the association of maximal expiratory pressure (MEP), maximal inspiratory pressure (MIP), and peak expiratory flow (PEF) with total duration of invasive mechanical ventilation (IMV) in subjects undergoing cardiac surgery.

BACKGROUND

Prolonged IMV is associated with respiratory infections, prolonged hospitalization, and increased mortality. Pulmonary function tests can help predict postoperative outcomes after cardiac surgery.

METHODS

We recruited subjects admitted for cardiac surgery. All MIP, MEP, and PEF measurements were performed before surgery. Multivariable analysis was performed using a multiple linear regression model to control for possible confounders and test for association of MIP, MEP, and PEF with IMV duration.

RESULTS

Overall, 125 subjects were included in the study. Higher MEP was associated with reduced duration of IMV after adjustment for confounders (P = 0.015), but no such association was observed between MIP or PEF and IMV.

CONCLUSIONS

In subjects undergoing elective cardiac surgery, preoperative MEP is associated with IMV duration.

Invasive Mechanical Ventilation in California Over 2000-2009: Implications for Emergency Medicine

INTRODUCTION

Patients who require invasive mechanical ventilation (IMV) often represent a sequence of care between the emergency department (ED) and intensive care unit (ICU). Despite being the most populous state, little information exists to define patterns of IMV use within the state of California.

METHODS

We examined data from the masked Patient Discharge Database of California's Office of Statewide Health Planning and Development from 2000-2009. Adult patients who received IMV during their stay were identified using the International Classification of Diseases 9th Revision and Clinical Modification procedure codes (96.70, 96.71, 96.72). Patients were divided into age strata (18-34 yr, 35-64 yr, and >65 yr). Using descriptive statistics and regression analyses, for IMV discharges during the study period, we quantified the number of ED vs. non-ED based admissions; changes in patient characteristics and clinical outcome; evaluated the marginal costs for IMV; determined predictors for prolonged acute mechanical ventilation (PAMV, i.e. IMV>96 hr); and projected the number of IMV discharges and ED-based admissions by year 2020.

RESULTS

There were 696,634 IMV discharges available for analysis. From 2000-2009, IMV discharges increased by 2.8%/year: n=60,933 (293/100,000 persons) in 2000 to n=79,868 (328/100,000 persons) in 2009. While ED-based admissions grew by 3.8%/year, non-ED-based admissions remained stable (0%). During 2000-2009, fastest growth was noted for 1) the 35-64 year age strata; 2) Hispanics; 3) patients with non-Medicare public insurance; and 4) patients requiring PAMV. Average total patient cost-adjusted charges per hospital discharge increased by 29% from 2000 (from $42,528 to $60,215 in 2014 dollars) along with increases in the number of patients discharged to home and skilled nursing facilities. Higher marginal costs were noted for younger patients (ages 18-34 yr), non-whites, and publicly insured patients. Some of the strongest predictors for PAMV were age 35-64 years (OR=1.12; 95% CI [1.09-1.14], p<0.05); non-Whites; and non-Medicare public insurance. Our models suggest that by 2020, IMV discharges will grow to n=153,153 (377 IMV discharges/100,000 persons) with 99,095 admitted through the ED.

CONCLUSION

Based on sustained growth over the past decade, by the year 2020, we project a further increase to 153,153 IMV discharges with 99,095 admitted through the ED. Given limited ICU bed capacities, ongoing increases in the number and type of IMV patients have the potential to adversely affect California EDs that often admit patients to ICUs.

Modified rapid shallow breathing index adjusted with anthropometric parameters increases predictive power for extubation failure compared with the unmodified index in postcardiac surgery patients

OBJECTIVE

The aim of this study was to determine the best predictors of successful extubation after cardiac surgery, by modifying the rapid shallow breathing index (RSBI) based on patients' anthropometric parameters.

DESIGN

Single-center prospective observational study.

SETTING

Two general intensive care units at a single research institute.

PARTICIPANTS

Patients who had undergone uncomplicated cardiac surgery.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The following parameters were investigated in conjunction with modification of the RSBI: Actual body weight (ABW), predicted body weight, ideal body weight, body mass index (BMI), and body surface area. Using the first set of patient data, RSBI threshold and modified RSBI for extubation failure were determined (threshold value; RSBI: 77 breaths/min (bpm)/L, RSBI adjusted with ABW: 5.0 bpm×kg/mL, RSBI adjusted with BMI: 2.0 bpm×BMI/mL). These threshold values for RSBI and RSBI adjusted with ABW or BMI were validated using the second set of patient data. Sensitivity values for RSBI, RSBI modified with ABW, and RSBI modified with BMI were 91%, 100%, and 100%, respectively. The corresponding specificity values were 89%, 92%, and 93%, and the corresponding receiver operator characteristic values were 0.951, 0.977, and 0.980, respectively.

CONCLUSIONS

Modified RSBI adjusted based on ABW or BMI has greater predictive power than conventional RSBI.

Predicting reintubation, prolonged mechanical ventilation and death in post-coronary artery bypass graft surgery: a comparison between artificial neural networks and logistic regression models

INTRODUCTION

In coronary artery bypass (CABG) surgery, the common complications are the need for reintubation, prolonged mechanical ventilation (PMV) and death. Thus, a reliable model for the prognostic evaluation of those particular outcomes is a worthwhile pursuit. The existence of such a system would lead to better resource planning, cost reductions and an increased ability to guide preventive strategies. The aim of this study was to compare different methods - logistic regression (LR) and artificial neural networks (ANNs) - in accomplishing this goal.

MATERIAL AND METHODS

Subjects undergoing CABG (n = 1315) were divided into training (n = 1053) and validation (n = 262) groups. The set of independent variables consisted of age, gender, weight, height, body mass index, diabetes, creatinine level, cardiopulmonary bypass, presence of preserved ventricular function, moderate and severe ventricular dysfunction and total number of grafts. The PMV was also an input for the prediction of death. The ability of ANN to discriminate outcomes was assessed using receiver-operating characteristic (ROC) analysis and the results were compared using a multivariate LR.

RESULTS

The ROC curve areas for LR and ANN models, respectively, were: for reintubation 0.62 (CI: 0.50-0.75) and 0.65 (CI: 0.53-0.77); for PMV 0.67 (CI: 0.57-0.78) and 0.72 (CI: 0.64-0.81); and for death 0.86 (CI: 0.79-0.93) and 0.85 (CI: 0.80-0.91). No differences were observed between models.

CONCLUSIONS

The ANN has similar discriminating power in predicting reintubation, PMV and death outcomes. Thus, both models may be applicable as a predictor for these outcomes in subjects undergoing CABG.